To study the possibility of cross-species transmission of CWD, two species of nonhuman primates, squirrel monkeys and cynomologus macaques, were infected orally or intracerebrally with brain material derived from CWD affected deer or elk. At the conclusion of FY08 seven of thirteen intracerebrally infected squirrel monkeys had developed clinical neurological signs and were confirmed by biochemical and pathological testing of brain to have a prion disease. One orally infected squirrel monkey has also developed disease. To this point no cynomologus macaques have developed any signs of disease. Observations on the remaining monkeys will continue for a few more years. During FY08 we inoculated four additional cynomologus macaques and squirrel monkeys with brain homogenates derived from a CWD infected squirrel monkey to evaluate the ability of CWD to adapt to a nonhuman primate host. In addition we are evaluating blood from infected squirrel monkeys for the presence of prion infectivity.[unreadable] [unreadable] Tissues from CWD-infected squirrel monkeys and CWD-infected cervids used to infect such monkeys are also being analyzed by titration in deer PrP expressing transgenic mice.